Search Publications
Wide-field Survey of Dwarf Satellite Systems around 10 Hosts in the Local Volume
Greene, Jenny E.; Beaton, Rachael L.; Carlsten, Scott G. +1 more
We present the results of an extensive search for dwarf satellite galaxies around 10 primary host galaxies in the Local Volume (LV, D < 12 Mpc) using archival CFHT/MegaCam imaging data. The hosts span a wide range in properties, with stellar masses ranging from that of the Large Magellanic Cloud to ∼3 times that of the Milky Way. The surveyed h…
The hot dayside and asymmetric transit of WASP-189 b seen by CHEOPS
Guterman, P.; Alonso, R.; Deleuil, M. +103 more
The CHEOPS space mission dedicated to exoplanet follow-up was launched in December 2019, equipped with the capacity to perform photometric measurements at the 20 ppm level. As CHEOPS carries out its observations in a broad optical passband, it can provide insights into the reflected light from exoplanets and constrain the short-wavelength thermal …
Optically thin spatially resolved Mg II emission maps the escape of ionizing photons
Chisholm, J.; Schaerer, D.; Henry, A. +2 more
Early star-forming galaxies produced copious ionizing photons. A fraction of these photons escaped gas within galaxies to reionize the entire Universe. This escape fraction is crucial for determining how the Universe became reionized, but the neutral intergalactic medium precludes direct measurement of the escape fraction at high redshifts. Indire…
Multiple populations in globular clusters and their parent galaxies
Da Costa, G. S.; Milone, A. P.; Cordoni, G. +14 more
The 'chromosome map' diagram (ChM) proved a successful tool to identify and characterize multiple populations (MPs) in 59 Galactic globular clusters (GCs). Here, we construct ChMs for 11 GCs of both Magellanic Clouds (MCs) and with different ages to compare MPs in Galactic and extragalactic environments, and explore whether this phenomenon is univ…
Helios-r2: A New Bayesian, Open-source Retrieval Model for Brown Dwarfs and Exoplanet Atmospheres
Apai, Dániel; Burgasser, Adam J.; Marley, Mark S. +5 more
We present an improved, hybrid CPU-GPU atmospheric retrieval code, Helios-r2, which is applicable to medium-resolution emission spectra of brown dwarfs, in preparation for precision atmospheric spectroscopy in the era of the James Webb Space Telescope. The model is available as open-source code on the Exoclimes Simulation Platform. We subject Heli…
The Sun is less active than other solar-like stars
Solanki, Sami K.; Reinhold, Timo; Shapiro, Alexander I. +4 more
The magnetic activity of the Sun and other stars causes their brightness to vary. We investigated how typical the Sun’s variability is compared with other solar-like stars, i.e., those with near-solar effective temperatures and rotation periods. By combining 4 years of photometric observations from the Kepler space telescope with astrometric data …
Revised and New Proper Motions for Confirmed and Candidate Milky Way Dwarf Galaxies
McConnachie, Alan W.; Venn, Kim A.
A new derivation of systemic proper motions of Milky Way satellites is presented and applied to 59 confirmed or candidate dwarf galaxy satellites using Gaia Data Release 2. This constitutes all known Milky Way dwarf galaxies (and likely candidates) as of 2020 May, except for the Magellanic Clouds, the Canis Major and Hydra 1 stellar overdensities,…
NuSTAR tests of sterile-neutrino dark matter: New Galactic bulge observations and combined impact
Wik, Daniel R.; Krivonos, Roman; Beacom, John F. +4 more
We analyze two dedicated NuSTAR observations with exposure ∼190 ks located ∼1 0 ° from the Galactic plane, one above and the other below, to search for x-ray lines from the radiative decay of sterile-neutrino dark matter. These fields were chosen to minimize astrophysical x-ray backgrounds while remaining near the densest region of the dark matter…
Diffuse and Pulsating Aurora
Miyoshi, Yoshizumi; Nishimura, Yukitoshi; Katoh, Yuto +14 more
This chapter reviews fundamental properties and recent advances of diffuse and pulsating aurora. Diffuse and pulsating aurora often occurs on closed field lines and involves energetic electron precipitation by wave-particle interaction. After summarizing the definition, large-scale morphology, types of pulsation, and driving processes, we review o…
Galaxy Merger Rates up to z ∼ 3 Using a Bayesian Deep Learning Model: A Major-merger Classifier Using IllustrisTNG Simulation Data
Conselice, Christopher J.; Ferreira, Leonardo; Duncan, Kenneth +3 more
Merging is potentially the dominant process in galaxy formation, yet there is still debate about its history over cosmic time. To address this, we classify major mergers and measure galaxy merger rates up to z ∼ 3 in all five CANDELS fields (UDS, EGS, GOODS-S, GOODS-N, COSMOS) using deep learning convolutional neural networks trained with simulate…